This invention relates to space thermostats, and particularly to programmable electronic space thermostats for controlling operation of a heating and/or cooling system according to a programmed time-temperature schedule.
Due to the recent emphasis on energy conservation, the replacement of existing conventional thermostats by thermostats having the capability of automatically controlling the temperature of a space of two or more different levels of temperature is becoming more popular. Accordingly, there are available on the market a wide variety of such replacement thermostats, sometimes referred to as set-back thermostats. Some of these set-back thermostats are basically electromechanical in that they utilize, for example, one or two bimetallic sensing elements coupled to a clock movement or timer. Others are basically electronic or solid state in that essentially all the components are electronic. Yet others are a combination of electromechanical and electronic components.
One particular electronic component utilized in some prior art set-back thermostats is a programmable microprocessor which offers considerable flexibility in establishing a desired time-temperature schedule. However, in known prior art devices incorporating a programmable microprocessor, the programming procedure that the homeowner must follow, in order to establish the desired time-temperature schedule, is extremely complicated.